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Objective: To explore the correlation between park view elements and their combinations on the heart rate (HR) and speed of walkers, joggers, and runners in different groups of people's profiles and walking types, provide suggestions for the planning and design of walking suitability of walking trails in parks, and guide people with different walking needs to scientifically choose walking trails in parks., Methods: Profile data and exercise data of users who recorded walking activities in Century Park are collected on Strava, and the park view images (PVIs) were taken and segmented semantically. Data are grouped according to gender, age, weight and exercise type, and the quantitative relationship between HR, speed and 17 park view elements is studied by Spearman correlation analysis., Results: (1) The influence of the same park view elements on the exercise physiological indicators of different genders is small; (2) Park view elements combination based on sky, grass-plant and tree can better stabilize the walking HR of the older adult; (3) Semi-enclosed trail dominated by tree can improve the walking HR and speed of people with larger body weight; (4) Natural routes dominated by sidewalk-path and supplemented by tree and sky elements are more suitable for walking, while the trails with larger sky area, no trees and wider trails are more suitable for running., Competing Interests: WW was employed by Shanghai Weilaichengshi Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Wei, Qian, Gao and Qiu.)

This study aims to investigate the influence of a new semi-rigid knee joint braces on kinematics using the Opti-knee knee joint kinematic analysis system at various exercise speeds. Twenty-four healthy young male adults were recruited for this study. Participants were randomly assessed while wearing and not wearing knee brace at four different speeds on a treadmill: normal walking (3.6 km/h), brisk walking (5.4 km/h), jogging (9 km/h), and moderate intensity running (10.8 km/h). Six degrees of freedom kinematic data from the knee joint were collected. Paired t-tests were conducted to calculate the kinematic differences. At speeds of 3.6 km/h and 5.4 km/h, wearing the knee brace led to reduced knee joint mobility in anterior-posterior translation, superior-inferior translation, internal-external rotation, and flexion-extension angles during the stance phase ( P < 0.05). At 9 km/h, wearing the brace reduced knee joint internal-external rotation and flexion-extension mobility during the stance phase ( P < 0.05). At 10.8 km/h, wearing the brace reduced knee joint flexion-extension mobility during the stance phase ( P < 0.05). Wearing brace has significant influence on knee kinematics at four speeds, and the effect of brace varies with the speed of movement.

Pronated feet have been associated with higher risks of running-related overuse injuries than neutral feet. However, it remains unclear why some pronated feet develop running-related injuries, while others do not. This study aimed to examine the differences in foot kinematics during jogging among individuals with symptomatic pronated feet (SP), asymptomatic pronated feet (AP) and asymptomatic neutral feet (AN). Thirty-nine recreational runners were recruited and classified into the SP, AP and AN groups. Statistical parametric mapping (SPM) and ANOVA were used to identify kinematic differences among three groups. The SPM results showed that the SP had larger forefoot abduction than the AN and AP during jogging, while three groups had similar rearfoot eversion during jogging. Both the AP and SP had larger forefoot sagittal range of motion (ROM) (mean difference = 3.5 and 4.8 deg, respectively) and smaller rearfoot sagittal ROM (mean difference = 5.0 and 3.5 deg, respectively) than the AN. Forefoot abduction during jogging may have the potential to identify pronated feet at greater risk of injury. Pronated feet, symptomatic or not, have comparable large forefoot sagittal ROM, i.e., arch deformation, compared to neutral feet. The findings could have implications for the injury aetiology and intervention strategies for SP.

Research attempted to validate simplified insoles with a reduced number of sensors to facilitate clinical application. However, the ideal sensor number is yet to be determined. The purpose was to investigate the validity of vertical ground reaction forces in various simplified pressure sensor insoles and to identify an optimal compromise between sensor number and measurement performance. A Kistler force plate (1000 Hz) and 99-sensor Pedar-X insole (100 Hz) obtained force data of 15 participants during walking and jogging. Eight simplified insole layouts (3-17 sensors) were simulated. Layout performances were expressed as Pearson's correlation coefficients ( r ) with force plate as reference and coefficient of variation. Differences were assessed via repeated-measures ANOVA as partial eta square ( η p 2 ) at p < .05. All layouts correlated with the force plate ( r = .70-.99, p < .01). All layout performances were higher in jogging than in walking by r = +.07 ± .04 ( η p 2 =.28-.66, p < .05). The three- and five-sensor layouts yielded the lowest correlation ( r = .70-.88) and the highest coefficient of variation (11-22%). Layout performances improved constantly from 7 to 11 sensors. The optimal compromise between simplification and measurement performance, quantified via change in correlation per sensor number, was found in the 11-sensor layout, recommendable for practical settings to improve monitoring and adjusting protocols.

Gastrocnemius weakness is associated with Achilles tendinopathies and muscle strains, with the medial gastrocnemius (MG) more commonly injured than the lateral gastrocnemius (LG). Walking and jogging are common in daily activities and sports, and biomechanical differences between shod and barefoot exercise may influence MG and LG activation. Understanding these activation patterns could help optimize training programs for injury prevention and/or rehabilitation. The aim was to compare MG and LG electromyographic activity during walking and jogging, both shod and barefoot. Twenty-nine participants (25.28 ± 4.53 years, 171.31 ± 0.76 cm, 72.68 ± 6.36 kg) completed a warm-up followed by 1 min of walking (80-99 steps/min) and jogging (130-150 steps/min) in both conditions (barefoot and shod, random order). Electromyographic signals were recorded using wearable devices (mDurance Solutions S.L., Granada, Spain; 1024 Hz sampling rate). We measured the root-mean-square (RMS) amplitudes for an entire stride cycle and digitally filtered the signals. For analysis, we normalized electromyographic values to the average peak values obtained during two sprints. We analyzed differences with a repeated-measures analysis of variance. Significant effects of condition (barefoot-shod) and gastrocnemius (MG-LG) were observed (all p ≤ 0.023, ƞp 2  = 0.17-0.39), with higher MG activation compared to LG in the barefoot conditions (p = 0.004-0.027, d = 0.72-0.83), and nonsignificant differences between muscles in the shod conditions (p > 0.05). Shod exercise compared to barefoot resulted in lower MG activation (p = 0.001-0.003, d = 0.62-0.63) and non-significant differences in LG activation. These results indicate that barefoot walking and jogging increase MG activation compared to shod conditions, with no differences in LG activation. Additionally, footwear reduces differences between MG and LG., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objective: Limited research has directly compared the effectiveness of aqua- and land-based exercises for postexercise recovery. This study aimed to fill this gap by comparing the effects of these 2 types of exercises on postexercise recovery., Methods: Sixteen male college athletes participated in an 8-day experimental study. The initial 2 days were dedicated to determining the intensity levels for the muscle-damaging exercise and recovery jogging. In a crossover design, participants underwent 2 sets of experimental trials. They were randomly assigned to either an aqua or land recovery intervention for days 3 to 5, and after a 1-week washout period they switched to the opposite intervention for days 6 to 8. Muscle soreness, creatine kinase, anaerobic performance, countermovement-jump height, and flexibility were assessed at different time points: baseline, immediately after downhill running, within 1 hour after jogging, and 24 hours and 48 hours after aqua or land jogging., Results: Significant group × time interaction effects were detected in the perceived soreness of the hamstring and quadriceps. However, the post hoc analysis showed no significant difference between aqua and land jogging groups. No significant group × time interaction effect was observed in creatine kinase, anaerobic performance, countermovement-jump height, or flexibility., Conclusion: Aqua and land jogging have similar recovery effects on muscle soreness and performance-based parameters.

The objective was to compare simplified pressure insoles integrating different sensor numbers and to identify a promising range of sensor numbers for accurate center of pressure (CoP) measurement. Twelve participants wore a 99-sensor Pedar-X insole (100 Hz) during walking, jogging, and running. Eight simplified layouts were simulated, integrating 3-17 sensors. Concordance correlation coefficients (CCC) and root mean square errors (RMSE) between the original and simplified layouts were calculated for time-series mediolateral (ML) and anteroposterior (AP) CoP. Differences between layouts and between gait types were assessed via ANOVA and Friedman test. Concordance between the original and simplified layouts varied across layouts and gaits (CCC: 0.43-0.98; χ(7)2 ≥ 34.94, p < 0.001). RMSE ML and RMSE AP [mm], respectively, were smaller in jogging (5 ± 2, 15 ± 9) than in walking (8 ± 2, 22 ± 4) and running (7 ± 4, 20 ± 7) (ηp2: 0.70-0.83, p < 0.05). Only layouts with 11+ sensors achieved CCC ≥ 0.80 in all tests across gaits. The 13-sensor layout achieved CCC ≥ 0.95 with 95% confidence, representing the most promising compromise between sensor number and CoP accuracy. Future research may refine sensor placement, suggesting the use of 11-13 sensors. For coaches, therapists, and applied sports scientists, caution is recommended when using insoles with nine or fewer sensors. Consulting task-specific validation results for the intended products is advisable.

Background: The present investigation aimed to examine the movement patterns and cardiometabolic demand during jogging football (JF), which is a new concept of recreational football that allows walking and jogging with limiting running behavior., Methods: Twenty-three collegiate soccer players played soccer for 10 minutes while following three different rules: 1) the players moved by walking only (walking football [WF]); 2) the players moved by walking or jogging (JF); and 3) the players moved freely, i.e., a combination of walking, jogging, and running (usual football [UF]). A graded exercise test (GXT) was performed to determine individual relationships between heart rate (HR) and moving speeds., Results: The HR, metabolic equivalents (METs), and velocity differed significantly in the three conditions and significantly increased in the order of WF, JF, and UF (P<0.001). The speed was significantly higher in the recreational football compared to that in the GXT, but METs were significantly higher in all forms of recreational footballs than in the GXT (P<0.05). Based on the results of JF, the duration of the movement at the speed of <5 km/h was significantly shorter than that of WF, and that at speed of >10km/h, it was significantly shorter than that of UF (P<0.05)., Conclusions: The present investigation revealed the characteristics of the activity profiles of JF in comparison to WF and UF. JF is a recreational sport with an exercise intensity that falls between WF and UF, owing to the shorter durations of walking and running.

Many studies have demonstrated that outdoor physical activity positively affects the physical health of young people. Here, we aimed to examine the extent to which outdoor jogging was associated with the physical health of youths, and then to decipher whether a dose-response relationship exists between them. A total of 2852 youths from a Chinese university were enrolled in a long-term experimental study between September 2018 and September 2019. We conducted two waves of physical health tests for 2852 youths (before and after the jogging interventions in 2018 and 2019, respectively) using China's National Student Physical Health Standard (NSPHS). Paired t -tests were used to examine statistical differences. A multiple regression model was used to evaluate the associations between jogging and physical health. The results showed that: statistically significant changes in the two waves of physical health outcomes were suggested after jogging interventions; outdoor jogging in campus green space was associated with participants' physical health after controlling for covariates; and a dose-response relationship between jogging and physical health outcomes was revealed, with 120-140 km/year (approximately 3.43-4 km/week) being the most effective intervention dose. Our findings have implications for promoting physical health in youth groups by encouraging outdoor physical activity.

Background: While increased face mask use has helped reduce COVID-19 transmission, there have been concerns about its influence on thermoregulation during exercise in the heat, but consistent, evidence-based recommendations are lacking., Hypothesis: No physiological differences would exist during low-to-moderate exercise intensity in the heat between trials with and without face masks, but perceptual sensations could vary., Study Design: Crossover study., Level of Evidence: Level 2., Methods: Twelve physically active participants (8 male, 4 female; age = 24 ± 3 years) completed 4 face mask trials and 1 control trial (no mask) in the heat (32.3°C ± 0.04°C; 54.4% ± 0.7% relative humidity [RH]). The protocol was 60 minutes of walking and jogging between 35% and 60% of relative VO 2max . Rectal temperature (T rec ), heart rate (HR), temperature and humidity inside and outside of the face mask (T micro&#95;in , T micro&#95;out , RH micro&#95;in , RH micro&#95;out ) and perceptual variables (rating of perceived exertion (RPE), thermal sensation, thirst sensation, fatigue level, and overall breathing discomfort) were monitored throughout all trials., Results: Mean T rec and HR increased at 30- and 60-minute time points compared with 0-minute time points, but no difference existed between face mask trials and control trials ( P > 0.05). Mean T micro&#95;in , RH micro&#95;in , and humidity difference inside and outside of the face mask (ΔRH micro ) were significantly different between face mask trials ( P < 0.05). There was no significant difference in perceptual variables between face mask trials and control trials ( P > 0.05), except overall breathing discomfort ( P < 0.01). Higher RH micro&#95;in , RPE, and thermal sensation significantly predicted higher overall breathing discomfort ( r 2 = 0.418; P < 0.01)., Conclusion: Face mask use during 60 minutes of low-to-moderate exercise intensity in the heat did not significantly affect T rec or HR. Although face mask use may affect overall breathing discomfort due to the changes in the face mask microenvironment, face mask use itself did not cause an increase in whole body thermal stress., Clinical Relevance: Face mask use is feasible and safe during exercise in the heat, at low-to-moderate exercise intensities, for physically active, healthy individuals.

Background: Being a major cardiovascular risk factor, dyslipidemia is a critical problem in public health. Recommendations in performing regular physical exercise are important to prevent dyslipidemia., Methods: Based on a discovery cohort with 27,735 subjects and a replication cohort with 67,512 subjects, we evaluated the associations of regularly performing 23 exercises with 4 dyslipidemia indices measured from serum, including triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and TG/HDL-C ratio. Regular exercise was defined as performing 30 min of "exercise" three times a week. "Exercise" includes leisure-time activities such as jogging, swimming, etc. Sex, age, body mass index, alcohol drinking, cigarette smoking, and education level were adjusted in all statistical analyses., Results: Among the 23 exercises, only jogging was associated with a decreased level of TG (95% confidence interval [C.I.] = 5.9-14.5 mg/dL) and TG/HDL-C ratio (95% C.I. = 0.22-0.49). A total of 5 exercises were associated with an increased level of HDL-C, including jogging (95% C.I. = 2.1-3.3 mg/dL), swimming (95% C.I. = 1.6-3.3 mg/dL), dance dance revolution (95% C.I. = 1.5-3.4 mg/dL), international standard dancing (95% C.I. = 1.0-2.7 mg/dL), and cycling (95% C.I. = 0.6-1.8 mg/dL). These significant findings were further well replicated in the cohort of 67,512 subjects., Conclusion: Regular jogging was not only associated with an increased level of HDL-C, but also the only one exercise associated with a decreased level of TG and TG/HDL-C ratio. Nonetheless, jogging may be difficult to engage in for subjects with limited exercise capacity. We here found that swimming, dancing, and cycling are also significantly associated with an increased level of HDL-C. People who are seeking exercise to improve their lipoprotein-lipid profiles can have other choices now.

Purpose: The aims of this project were twofold: 1) to assess the concurrent validity of raw accelerometer outputs with ground reaction forces (GRF) and loading rates (LR) calculated from force plate across a range of simulated habitual PA and 2) to identify the optimal wear site among the ankle, hip, and wrist with the strongest relationships between accelerometer and force plate and/or skeletal outcomes., Methods: Thirty healthy young adults (23.0 ± 4.5 yr, 50% female) wore a triaxial accelerometer at the right ankle, hip, and wrist while performing eight trials of walking, jogging, running, low box drops, and high box drops over an in-ground force plate. Repeated-measures correlations and linear mixed models were used to assess concurrent validity of accelerometer and force plate outcomes across wear sites., Results: Strong repeated-measures associations were observed between peak hip resultant acceleration and resultant LR (rrm 1169 = 0.74, P < 0.001, 95% confidence interval = 0.718, 0.769) and peak hip resultant accelerations and resultant GRF (rrm 1169 = 0.69, P < 0.001, 95% confidence interval = 0.660, 0.720) when data were combined across activities. By contrast, small to moderate associations were seen between ankle-based outcomes and corresponding GRF and LR during walking and jogging (rrm 209 = 0.17-0.34, all P < 0.001). No significant associations were seen with wrist-based outcomes during any activity. In addition, linear mixed models suggested that 24%-50% of the variability in peak GRF and LR could be attributed to measured accelerations at the hip., Conclusion: Peak accelerations measured at the hip were identified as the strongest proxies for skeletal loading assessed via force plate., (Copyright © 2020 by the American College of Sports Medicine.)

Foot temperature during activities of daily living affects the human performance and well-being. Footwear thermal characteristics affect the foot temperature inside the shoe during activities of daily living. The temperate at the sole of the foot (plantar temperature) is influenced by different thermal properties such as heat capacity, heat diffusivity, and thermal conductivity of the shoe sole in addition to its mechanical properties. Hence the purpose of this study was to propose a method to allow investigating the effect of footwear thermal characteristics on the foot temperature during activities of daily living, like walking or jogging. The transient heat transfer between the foot and the ground was studied to drive the governing equation for heat transfer modelling in footwear and to predict foot sole temperature during walking, and jogging. Different thermo-mechanical properties of shoe sole, as well as geometrical parameters, were investigated. The proposed model showed to be able to adequately predict the plantar temperature at the ball of the foot when compared to the results from experimental measurements. Finally, using the proposed method, the thermal behaviour of two different shoes with two different sole materials EVA08 and EVA12 were compared. It was shown that heat capacity as compared to the thermal conductivity of the shoe sole is more effective in reducing the plantar temperature increase in short term. The proposed method proved to be able to accurately predict the thermal behaviour of shoes and can provide a tool to predict footwear thermal comfort., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Purpose: Physical exercise has been shown to be effective in reducing stereotypic behaviors in children with autism spectrum disorder. One possible mechanism concerns the matching hypothesis between exercise and behavior. The present study sought to examine this matching exercise-behavior relationship., Methods: Participants (N = 21, 17 males and 4 females, Mage = 11.07 ± 1.44 yr, Mheight = 1.46 ± 0.99 m, and Mweight = 40.60 ± 8.25 kg), with observable forms of hand-flapping and body-rocking stereotypic behaviors, underwent three separate days of conditions, one for the control condition, one for the 10-min ball-tapping exercise condition, and one for the 10-min jogging condition, in a randomized order. The frequency of each type of stereotypic behavior was videotaped from 15 min before to 60 min after the exercise., Results: Results revealed that only hand-flapping stereotypic behaviors were significantly reduced in the ball-tapping exercise condition (P < 0.017), whereas only body-rocking stereotypic behaviors were significantly reduced in the jogging exercise condition (P < 0.017). However, the behavioral benefit diminished at 45 min after the respective exercise., Conclusion: Physical exercise should be topographically matched with stereotypic behavior to produce desirable behavioral benefits in children with autism spectrum disorder., (Copyright © 2020 by the American College of Sports Medicine.)

An affordable player monitoring solution could make the evaluation of external loading more accessible across multiple levels of football (soccer). The present study aimed to determine the accuracy of a newly designed and low-cost Global Positioning System (GPS) whilst performing match-specific movement patterns. Sixteen professional male football players (24 ± 3 years) were assigned a GPS device (TT01, Tracktics GmbH, Hofheim, Germany) and completed two experimental trials. In each trial, a continuous protocol including seven movements (sideways cornering, diagonal cornering, accelerating, decelerating, backwards jogging, shuttle running, and skipping) adding up to 500 m, was completed. Time-motion data was compared with criterion distance and velocity (photo-cell timing gates and radar). Validity was assessed through the standard error of the estimate (SEE) and reliability through the coefficient of variation (CV; both with 95% confidence limits). For the total distance covered during the protocol, the system was found to be valid (SEE = 3.1% [2.2; 5.8]) and reliable (intra-device CV = 2.0% [1.2; 7.6]). Similar results were found for velocity (SEE = 3.4% [2.6; 4.8], CV = 4.7% [3.2; 8.5]). In conclusion, the present GPS system, a low-cost solution, was found to be a valid and reliable tool for measuring physical loading during football-specific movements., (© Journal of Sports Science and Medicine.)

Background: Quadriceps strength recovery after anterior cruciate ligament (ACL) reconstruction is an important criterion for progress in rehabilitation and return to sports. The purpose of this study was to determine whether quadriceps strength to body weight ratio (QS/BW) is a significant indicator for initiating jogging after ACL reconstruction., Methods: Isokinetic quadriceps strength at 60°/s was measured and a jogging trial was completed 3 months after ACL reconstruction with hamstring tendon autograft in 83 patients (36 male, 47 female; mean age, 26.6 ± 12.4 years). Based on the jogging trial results, patients were assigned to either a successful jogging group (mean velocity ≥ 9 km/h) or an unsuccessful jogging group (mean velocity < 9 km/h). The association between QS/BW and successful jogging after surgery was investigated by multivariate logistic regression analysis and the cut-off value was determined by receiver operating characteristic analysis., Results: Forty-four patients (53.0%) were assigned to the successful jogging group and 39 (47.0%) to the unsuccessful jogging group. QS/BW was independently associated with initiating jogging 3 months after surgery. The cut-off value of QS/BW for successful jogging was 1.45 Nm/kg (area under the curve = 0.94; sensitivity = 88.6%, specificity = 87.2%). All of the patients who initiated jogging with QS/BW of > 1.45 Nm/kg at 3 months returned to sports without recurrence or contralateral injury by 10 months after surgery., Conclusions: QS/BW is a significant indicator for safely initiating jogging 3 months after ACL reconstruction. The cut-off value of QS/BW for initiating jogging was 1.45 Nm/kg., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

We examined the effects of long-term exercise on age-related decline in static balance control through centre-of-pressure (CoP) measurements of four groups of participants: older controls, younger controls, older Tai Chi exercisers and older joggers. The participants stood quietly in a tandem stance on a force platform for 30 s with eyes open (EO) and eyes closed (EC). The older controls showed remarkably larger CoP and EC/EO ratios than younger controls and older Tai Chi exercisers. The EC/EO ratios of velocity in the mediolateral direction of older joggers were significantly smaller than those of older controls. Results suggest that the static balance of older controls showed a significant decline caused by age-related changes. Long-term Tai Chi and jogging, particularly the former, contributed to static balance control in older people. Older adults relied more on visual information in static postural control than young people. Tai Chi would be an ideal exercise for improving static balance in older people.

This study quantified the match-play activity profiles of international touch rugby and different positional physical outputs in comparison with training specificity. Between November 2019 and January 2020, 82 half-matches and 173 training global positioning system data from 16 national male touch rugby players (mean ± SD: age 23.71 ± 3.90 years, height 1.73 ± 0.05 m, weight 65.38 ± 9.08 kg, touch rugby training experience 6.09 ± 3.31 years) were recorded. The distance covered by wings in half-match (1676.66 ± 444.80 m) was more than that of link (1311.35 ± 223.59 m) and middle (1383.52 ± 246.55 m) by a large effect (partial η 2 = 0.19), which was mainly attributed to walking and jogging (< 4.00 m·s -1 ). Meanwhile, the middles covered more running distance (4.00-5.50 m·s -1 ) than other positions. No significant positional group difference was observed for distance covered >5.50 m·s -1 , maximum velocity, and the ratio of acceleration and deceleration in matches. Training intensity was close to the match-play outputs only for the high-speed running distance at ≥ 5.50 m·s -1 . However, the training activity pattern consistently showed a disparity with the match-play outputs, in terms of shorter normalized training distance covered, less recovery distance covered at ≤ 5.50 m·s -1 , higher maximum velocity, and heavier weighting to acceleration in training activities. The current study highlights for the first time that in-match deceleration capacity and active recovery pacing strategy may be essential to touch rugby players. The data provided practitioners a deeper understanding of the physical demands of national touch rugby and allowed them to align the training with the match-play intensity., (© Journal of Sports Science and Medicine.)

To compare demands of national netball umpires between levels of competition, 22 Netball New Zealand high-performance umpires participated in this investigation. These included from highest to lowest standard: 9 × semi-professional ANZ Championships (ANZC); 6 × National A Squad (NZA); and 7 × National Development Squad (DEV). Physical (global positioning system tri-axial accelerometry), physiological (heart rate) and technical (video analysis) demands were determined for 48 (16 per group) umpire match performances. Level of competition had no significant effect on physical or mean physiological demands. However, ANZC umpires spent a lower proportion of time at low heart rates compared to DEV, and a greater proportion of time at high, rather than moderate, heart rates compared to NZA. Compared to lower standard umpires, ANZC spent lesser proportions of time standing but greater proportions of time walking backwards and sideways, and turning to change direction. Furthermore, ANZC umpires spent lower proportions of time jogging, but greater proportions of time sprinting compared to DEV. Finally, ANZC umpires spent longer mean durations than DEV on the goal third side line. As such, the difference in demands experienced by national netball umpires between levels of competition is more technical than physical or physiological.

A means of quantifying continuous, free-living energy expenditure (EE) would advance the study of bioenergetics. The aim of this study was to apply a non-linear, machine learning algorithm (random forest) to predict minute level EE for a range of activities using acceleration, physiological signals (e.g., heart rate, body temperature, galvanic skin response), and participant characteristics (e.g., sex, age, height, weight, body composition) collected from wearable devices (Fitbit charge 2, Polar H7, SenseWear Armband Mini and Actigraph GT3-x) as potential inputs. By utilising a leave-one-out cross-validation approach in 59 subjects, we investigated the predictive accuracy in sedentary, ambulatory, household, and cycling activities compared to indirect calorimetry (Vyntus CPX). Over all activities, correlations of at least r = 0.85 were achieved by the models. Root mean squared error ranged from 1 to 1.37 METs and all overall models were statistically equivalent to the criterion measure. Significantly lower error was observed for Actigraph and Sensewear models, when compared to the manufacturer provided estimates of the Sensewear Armband (p < 0.05). A high degree of accuracy in EE estimation was achieved by applying non-linear models to wearable devices which may offer a means to capture the energy cost of free-living activities.

Coker, NA, Wells, AJ, and Gepner, Y. The effect of heat stress on measures of running performance and heart rate responses during a competitive season in male soccer players. J Strength Cond Res 34(4): 1141-1149, 2020-Measures of running performance and heart rate (HR) responses to match play during 3 different heat stress (HS) conditions were assessed in 7 National Collegiate Athletic Association (NCAA) Division I male soccer players. Total distance and distance covered within distinct velocity zones (walking [WALK], jogging [JOG], low-speed running, high-speed running, sprinting [SPRINT], low-intensity running [LIR], and high-intensity running [HIR]) were assessed using global positioning system units for more than 12 matches. Heat stress was monitored during each match, and matches were defined as low (HSlow, n = 4), moderate (HSmod, n = 4), or high (HShigh, n = 4) HS. Minutes played were significantly different across HS conditions (p = 0.03). Therefore, distance covered within each movement velocity was assessed relative to minutes played and as a percentage of total playing time. WALKrel was significantly greater during HShigh compared with HSlow (p = 0.035). LIRrel was significantly greater during HSmod (p = 0.015) compared with HSlow. A trend was observed for %WALK being higher during HShigh compared with HSlow (p = 0.066). %LIR was significantly greater during HShigh compared with HSlow (p = 0.048). High-intensity running was not significantly different across HS conditions. Percent of time spent >85% HRmax was significantly greater during HShigh (p = 0.002) and HSmod (p < 0.001) compared to HSlow. Percent of time spent between 65-84% HRmax was significantly greater during HSlow compared to HShigh (p < 0.001). Results indicate that HS resulted in increased LIR and %HR≥85, while HIR was maintained. High-intensity running performance may be conserved through decreased playing time or the adoption of pacing strategies. This may assist coaches in altering player management strategies to optimize team performance.

Harry, K and Booysen, MJ. Faster heart rate recovery correlates with high-intensity match activity in female field hockey players-training implications. J Strength Cond Res 34(4): 1150-1157, 2020-The physical match demands of female field hockey are intense and may differ according to playing positions. In addition, conducting sports-specific field tests can assist coaches in determining their players' preparedness for competition. There is limited research regarding the match demands and relevance of field testing at premier league levels. Therefore, the aims were to describe the physical match demands of female premier league (amateur) field hockey, and to determine the relationships between match activity patterns and physical performance tests. Match activity and heart rate data were collected from 32 female participants using the Zephyr BioHarness 3 system. Participants also performed the Yo-Yo intermittent recovery (level 1) (n = 22), repeated sprint ability (n = 21), and the heart rate recovery (n = 16) tests. Moderate to large effect sizes were observed when defenders were compared with midfielders and forwards for time spent (%) in standing/walking and jogging (d = 0.64-1.30) in addition to the playing time (%) spent in the low-to-moderate and very high heart rate zones (d = 0.69-0.85). Heart rate recovery (10 s) correlated with the playing time (%) spent in sprinting (r = 0.73, p = 0.002). Heart rate recovery (60 s) and the Yo-Yo intermittent recovery test both correlated with the playing time (%) spent in running (r = 0.77, p = 0.0006 and r = 0.54, p = 0.01). The differences in physical match demands between positions emphasize the importance of training specificity at premier league levels. The heart rate recovery test can be used to assess a female field hockey player's capability to perform high-intensity match activity.

Rawcliffe, AJ, Graham, SM, Simpson, RJ, Moir, GL, Martindale, RJ, Psycharakis, SG, and Connaboy, C. The effects of British Army footwear on ground reaction force and temporal parameters of British Army foot drill. J Strength Cond Res 34(3): 754-762, 2020-High rates of occupational training-related lower-limb musculoskeletal (MSK) overuse injuries are reported for British Army recruits during basic training. Foot drill is a repetitive impact loading occupational activity and involves striking the ground violently with an extended-knee (straight-leg) landing. Foot drill produces vertical ground reaction force (vGRF) equal to or greater than those reported for high-level plyometric exercises/activities. Shock absorbing footwear aid in the attenuation of the magnitude of vGRF, resulting in a reduced risk of lower-limb MSK overuse injury when running. The potential shock absorbing characteristics of standard issue British Army footwear on the magnitude of vGRF and temporal parameters of foot drill are scant. Therefore, this study sought to determine the magnitude of and examine changes in vGRF and temporal parameters of foot drill across 3 types of British Army footwear. Sampled at 1,000 Hz, the mean of 8 trials from 15 recreationally active men were collected from 4 foot drills; stand-at-ease, stand-at-attention, quick-march (QM), and halt. Analysis of a normal walk was included to act as a comparison with QM. Significant main effects (P ≤ 0.05) were observed between footwear and foot drill. The training shoe (TR) demonstrated significantly greater shock absorbing capabilities when compared with the combat boot and ammunition boot. Foot drill produced peak vGRF and peak vertical rate of force development in excess of 5 bw, and 350 bw·s, respectively. Time to peak vGRF ranged from 0.016 to 0.036 ms across foot drills, indicating that passive vGRF may not be under neuromuscular control. The marginal reductions in the magnitude of vGRF and temporal parameters in foot drill associated with the TR may act to reduce the accumulative impact loading forces experienced by recruits, subsequently minimizing the severity and rates of lower-limb MSK overuse injuries and recruit medical discharges during basic training.

Objectives　The number of elderly joggers/runners in Japan has been on the rise. This study aimed to investigate the practice of jogging/running activity, features of quality of life (QOL) among the elderly, and the relationships between jogging/running activity and QOL features.Methods　A questionnaire survey was conducted with 83 older adults aged 60-81 who had participated in 7 marathons held from November 2014 to July 2015. Sex, age, experience (years), mileage (kms/month), frequency of jogging/running activity (times/week), frequency of participation in marathons (times/year), and QOL were assessed. QOL was measured with the WHOQOL26, which is composed of "overall QOL", "physical," "psychological," "social relationships," and "environment." The relations between these variables were estimated using correlation and multiple regression analyses.Results　In the majority of the participants, experience was 5 or more years, mileage was less than 150 kms/month, frequency of jogging/running activity was 1-4 times a week, and frequency of participation in marathons was 1-10 times a year. As for the participants above the age of 65, the mean QOL for men was 3.8 (standard deviation (SD)=0.4) and for women was 4.1 (SD=0.5). These scores were higher than those previously reported in studies among Japanese older adults. And there was no evidence which showed the bodily pain such as lower limb disorders, which older joggers or runners may often get. Overall QOL was positively associated with age and frequency of jogging/running activity. The social relationships domain was positively associated with sex and experience. The environment domain was positively correlated with experience. All these associations were significant.Conclusions　The results suggest that among the elderly, a high frequency and/or experience of jogging/running activity is significantly associated with a high level of QOL. In the future, a case-control or longitudinal study with a larger sample size and/or more variables is required to obtain a more definitive interpretation of the present findings.

Context: Foam-rolling exercises are frequently included in warmups due to their benefits for increasing range of motion (ROM). However, their effects on proprioception and vertical jump have not been analyzed and therefore remain unclear. Moreover, the effects of performing practical-duration foam-rolling exercises after typical warmup exercises such as jogging are unknown., Objective: To analyze the effects of jogging and practical-duration foam-rolling exercises on the ROM, knee proprioception, and vertical jump of athletes., Design: Randomized controlled study., Setting: Sports laboratory and university track., Patients or Other Participants: Thirty athletes were randomly classified into an experimental group (EG) or control group (CG)., Intervention(s): The EG performed 8-minute jogging and foam-rolling exercises. The CG performed 8-minute jogging., Main Outcome Measure(s): Knee flexion, hip extension, active knee extension, ankle dorsiflexion (ADF), knee-joint position sense, and countermovement jump (CMJ) were evaluated before the intervention (baseline), after (post 0 min), and 10 minutes later., Results: The EG exhibited higher values for ADF and CMJ at post 0 min (ADF: P < .001, d = 0.88; CMJ: P < .001, d = 0.52) and 10 minutes later (ADF: P = .014, d = 0.41; CMJ: P = .006, d = 0.22) compared with baseline. Although the CG also showed increased CMJ at post 0 min ( P = .044, d = 0.21), the EG demonstrated a greater increase ( P = .021, d = 0.97). No differences were found in the remaining ROM variables (knee flexion, hip extension, active knee extension: P values > .05). For knee-joint position sense, no differences were found ( P > .05)., Conclusions: Combining jogging and practical-duration foam rolling may increase ADF and CMJ without affecting knee proprioception and hip or knee ROM. Jogging by itself may slightly increase ADF and CMJ, but the results were better and were maintained after 10 minutes when foam rolling was added.

Joo, CH and Jee, H. Activity profiles of top-class players and referees and accuracy in foul decision-making during Korean national league soccer games. J Strength Cond Res 33(9): 2530-2540, 2019-The aims of this study were to compare the activity profiles between the top-class referees and players and elucidate the factors related to foul decision-making. Three hundred thirty-five elite-level players and referees were analyzed for distance covered during 20 matches of nationally held 2016 Korean league competitions. Distance covered by the players and referees was analyzed for the activity zones (slow walking, walking, jogging, running, high-intensity running, and sprinting) and 15-minute match periods. Mean distance between foul play and referee locations, foul plays, and 15-minute match periods were compared with the foul decision errors. Foul play and decision error rates (%) were also analyzed per segmented pitch zone. Although the total distance covered during a match and distances covered by jogging, running, and sprinting were significantly different between the players and referees, differences were within 1%. Significant differences in the distance covered before and after halftime were observed. The greatest distance between the foul play and referee locations, number of foul plays, and number of foul decision errors were observed at the 75-minute match period. Finally, the greater number of foul plays was observed in the neutral and attacking zones, and the foul decision errors were observed in the right defensive and left attacking zones 1. In conclusion, although the activity profiles may be different, referees should maintain certain level of physical fitness to match that of the players. To reduce the number of foul decision errors, factors such as match time, foul occurring location, and distance between foul play and referee locations should be considered.

Purpose: To evaluate the effects of probiotic supplementation on gastrointestinal (GI) symptoms, circulatory markers of GI permeability, damage, and markers of immune response during a marathon race., Methods: Twenty-four recreational runners were randomly assigned to either supplement with a probiotic (PRO) capsule [25 billion CFU Lactobacillus acidophilus (CUL60 and CUL21), Bifidobacterium bifidum (CUL20), and Bifidobacterium animalis subs p. Lactis (CUL34)] or placebo (PLC) for 28 days prior to a marathon race. GI symptoms were recorded during the supplement period and during the race. Serum lactulose:rhamnose ratio, and plasma intestinal-fatty acid binding protein, sCD14, and cytokines were measured pre- and post-races., Results: Prevalence of moderate GI symptoms reported were lower during the third and fourth weeks of the supplement period compared to the first and second weeks in PRO (p < 0.05) but not PLC (p > 0.05). During the marathon, GI symptom severity during the final third was significantly lower in PRO compared to PLC (p = 0.010). The lower symptom severity was associated with a significant difference in reduction of average speed from the first to the last third of the race between PLC (- 14.2 ± 5.8%) and PRO (- 7.9 ± 7.5%) (p = 0.04), although there was no difference in finish times between groups (p > 0.05). Circulatory measures increased to a similar extent between PRO and PLC (p > 0.05)., Conclusion: Probiotics supplementation was associated with a lower incidence and severity of GI symptoms in marathon runners, although the exact mechanisms are yet to be elucidated. Reducing GI symptoms during marathon running may help maintain running pace during the latter stages of racing.

Objectives: To determine the between-visit reliability of an accelerometer as a measure of lower-extremity impact acceleration at a variety of gait speeds in children., Design: Absolute reliability assessment., Methods: Ten children with no known gait pathology attended two testing sessions, three weeks apart. A tri-axial accelerometer was fixed to the child's distal tibia to measure peak positive acceleration responses while walking and running on the treadmill at three different speeds (comfortable walking, threshold walking, and jogging). Reliability of the average and standard deviation Peak Positive Acceleration (avgPPA and sdPPA, respectively) was calculated by intra-class correlation coefficients (ICC) and Minimum Detectable Change (MDC)., Results: Excellent reliability was indicated with ICC values for avgPPA of 0.90, 0.95, and 0.81 for comfortable walking, threshold walking, and jogging, respectively. Moderate reliability was found for the sdPPA measures. MDC values were calculated to be 18%, 26%, and 23% for comfortable walking, threshold walking, and jogging, respectively, indicating the amount by which an avgPPA value would need to change to ensure that the change is greater than a measurement error., Conclusions: An accelerometer attached to the distal tibia is practical for use in a clinical environment to collect lower extremity acceleration data in children. Clinicians can utilise this technique for assessing a change following an intervention, such as biofeedback gait retraining., (Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Purpose: To examine knee and hip biomechanics during walking and jogging in groups of ACLR patients at early, mid, and late time frames postsurgery and healthy controls., Methods: Participants included individuals with a history of primary, unilateral ACLR, stratified into early (1.4 ± 0.4 yr post, n = 18), mid (3.3 ± 0.6 yr post, n = 20), and late (8.5 ± 2.8 yr post, n = 20) ACLR groups based on time postsurgery, and a healthy control group (n = 20). Walking and jogging motion capture analysis of knee and hip kinetics and kinematics were measured in the sagittal and frontal planes. Interlimb (within groups) and between-group comparisons were performed for all gait variables. Statistical comparisons were made across the gait cycle by plotting graphs of means and 90% confidence intervals and identifying regions of the gait cycle in which the 90% confidence intervals did not overlap., Results: Early ACLR group demonstrated reduced knee flexion, knee extension, knee adduction, and hip adduction moments on the ACLR limb. Mid ACLR group demonstrated no gait differences between limbs or other groups. Late ACLR group demonstrated reduced knee flexion moments, and greater knee and hip adduction moments in their ACLR limb. Control group demonstrated no interlimb differences., Conclusions: Walking and jogging gait biomechanics presented differently in patients at different stages in time after ACLR surgery. The early ACLR group demonstrated lower sagittal and frontal plane joint loading on the ACLR limb compared with contralateral and control limbs. The mid ACLR group did not demonstrate any gait differences compared with the contralateral or control limb. The late ACLR group demonstrated lower sagittal plane joint loading compared with control limbs and greater frontal plane joint loading compared to contralateral and control limbs.

Curtis, RM, Huggins, RA, Looney, DP, West, CA, Fortunati, A, Fontaine, GJ, and Casa, DJ. Match demands of National Collegiate Athletic Association Division I men's soccer. J Strength Cond Res 32(10): 2907-2917, 2018-This study aimed to profile positional movement characteristics of National Collegiate Athletic Association (NCAA) Division I male soccer players. Eighteen Division I male soccer players were monitored using global positioning systems, inertial movement, and heart rate (HR) technology during 24 matches over a full competitive season (N = 235 observations). Positional groups were classified as either a forward (F), center midfielder (CM), wide midfielder (WM), or defender (D). Movement was profiled by locomotor (walking [0-7.19 km·h], jogging [7.20-14.39 km·h], running [14.40-21.59 km·h], and sprinting [>21.6 km·h]), and acceleration/deceleration characteristics (low intensity [0-1.99 m·s], moderate intensity [2-3.99 m·s], and high intensity [>4 m·s]). Players averaged distances of 9,367 ± 2,149 m per match at speeds of 91 ± 20 m·min and physiological intensities of 78 ± 8 %HRmax. Center midfielder demonstrated the highest average speeds (97 ± 20 m·min) and covered the most distance (9,941 ± 2,140 m). Wide midfielder accumulated the most sprint distance (391 ± 145 m) and high-intensity accelerations (129 ± 30 n)/decelerations (96 ± 24 n). Several practically meaningful differences exist between positions for internal and external load metrics. Match loads seen in NCAA Division I soccer vary from reports of professional soccer; however, the effects of match regulation, structure, and congestion, which are unique to NCAA soccer, require further investigation. Physical and physiological load monitoring of NCAA soccer may aid coaches and practitioners in the periodization of training programs leading up to and during a competitive soccer season. These data speak to the necessity for examining both internal and external loads by position.

Background: Hyperthermia often ends fatally and must therefore be promptly recognized and adequately treated., Case: A 28-year-old man participated in a long-distance race (3 km) on a hot summer day (28 °C). The runner collapsed, had to vomit but continued the run and reached the finish. Neurologically, the patient presented with intermittent cerebral seizures. External cooling batteries were immediately applied and cold infusions were started. The patient was admitted to the intensive care unit of the university hospital (body temperature 40.2 °C). After a few hours, a manifest disseminated intravascular coagulopathy developed with multiple organ failure. It took 12 l of volume replacement, 8 units of fresh frozen plasma and 2 units of erythrocyte concentrates in the first 12 h to stabilize the patient. Although with the help of forced external cooling and application of cold infusions, the body temperature could be lowered to 38 °C by the next morning, the overall situation of the patient continued to deteriorate. Despite dialysis and massive substitution of coagulation factors, the patient could not be sufficiently stabilized and died of brain edema., Conclusion: Not only the old or young children are subject to the potential danger of a fatal heat stroke but also young athletic persons after normal sports activities (3 km run). Cooling must be started immediately and the patient must be hospitalized as a vital emergency. If hemostasis fails due to the heat-related loss of hepatogenic protein synthesis, a viscious circle begins, which, as in the reported case, is irreversible despite maximum therapy and substitution.

Chronic ankle instability (CAI) is a condition resulting from a lateral ankle sprain. Shank-rearfoot joint-coupling variability differences have been found in CAI patients; however, joint-coupling variability (VCV) of the ankle and proximal joints has not been explored. Our purpose was to analyse VCV in adults with and without CAI during gait. Four joint-coupling pairs were analysed: knee sagittal-ankle sagittal, knee sagittal-ankle frontal, hip frontal-ankle sagittal and hip frontal-ankle frontal. Twenty-seven adults participated (CAI:n = 13, Control:n = 14). Lower extremity kinematics were collected during walking (4.83 km/h) and jogging (9.66 km/h). Vector-coding was used to assess the stride-to-stride variability of four coupling pairs. During walking, CAI patients exhibited higher VCV than healthy controls for knee sagittal-ankle frontal in latter parts of stance thru mid-swing. When jogging, CAI patients demonstrated lower VCV with specific differences occurring across various intervals of gait. The increased knee sagittal-ankle frontal VCV in CAI patients during walking may indicate an adaptation to deal with the previously identified decrease in variability in transverse plane shank and frontal plane rearfoot coupling during walking; while the decreased ankle-knee and ankle-hip VCV identified in CAI patients during jogging may represent a more rigid, less adaptable sensorimotor system ambulating at a faster speed.

The aim was to compare the physical characteristics of under-18 academy and schoolboy rugby union competition by position (forwards and backs). Using a microsensor unit, match characteristics were recorded in 66 players. Locomotor characteristics were assessed by maximum sprint speed (MSS) and total, walking, jogging, striding and sprinting distances. The slow component (<2 m · s -1 ) of PlayerLoad TM (PL slow ), which is the accumulated accelerations from the three axes of movement, was analysed as a measure of low-speed activity (e.g., rucking). A linear mixed-model was assessed with magnitude-based inferences. Academy forwards and backs almost certainly and very likely covered greater total distance than school forwards and backs. Academy players from both positions were also very likely to cover greater jogging distances. Academy backs were very likely to accumulate greater PL slow and the academy forwards a likely greater sprinting distance than school players in their respective positions. The MSS, total, walking and sprinting distances were greater in backs (likely-almost certainly), while forwards accumulated greater PL slow (almost certainly) and jogging distance (very likely). The results suggest that academy-standard rugby better prepares players to progress to senior competition compared to schoolboy rugby.

Purpose: To measure changes in anterior chamber structure before and after exercise in healthy individuals using anterior segment optical coherence tomography (ASOCT)., Methods: Thirty-two healthy young individuals performed jogging for 20 min. Eye blinking rate was recorded during rest and exercise. The anterior chamber angle (ACA), angle opening distance at 500 μm from the scleral spur (AOD500), trabecular-iris space area at 500 μm from the scleral spur (TISA500), iris concavity (IC), iris concavity ratio (CR), iris thickness at 750 μm from the scleral spur (IT750), anterior chamber depth (ACD), anterior chamber width (ACW), pupil diameter (PD), intraocular pressure (IOP), blood pressure (BP) and heart rate (HR) were recorded before and after exercise. Anterior chamber angle (ACA), AOD500, TISA500, IC, IT750, ACD, ACW and PD were measured with ASOCT., Results: Compared with rest, the blinking rate during exercise did not change significantly (13.04 ± 5.80 versus 13.52 ± 5.87 blinks/min, p = 0.645). The average IOP (15.4 ± 2.4 versus 12.4 ± 2.1 mmHg), ACA (35.96 ± 11.35 versus 40.25 ± 12.64 degrees), AOD500 (0.800 ± 0.348 versus 0.942 ± 0.387 mm), TISA500 (0.308 ± 0.155 versus 0.374 ± 0.193 mm 2 ), IC (-0.078 ± 0.148 versus -0.153 ± 0.159 mm) and CR (-0.027 ± 0.050 versus -0.054 ± 0.056) changed significantly (all p < 0.001), while the average IT750 (0.463 ± 0.084 versus 0.465 ± 0.086 mm; p = 0.492), ACD (3.171 ± 0.229 versus 3.175 ± 0.238 mm; p = 0.543) and ACW (11.768 ± 0.377 versus 11.755 ± 0.378 mm; p = 0.122) showed no significant change after exercise., Conclusion: The blinking rate did not change significantly during exercise, while ACA, AOD500 and TISA500 increased after exercise. Exercise also induced or increased IC. These changes in anterior chamber structure were only associated with exercise, but not with the postexercise change in PD or IOP., (© 2017 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

Objectives: The purpose of this study was to assess the validity of the ActiGraph GT3X+ (GT3X+) and the BodyMedia SenseWear Armband (SWA) to estimate energy expenditure (EE) during physical activity and field sport movements., Design: Criterion validity., Methods: Twenty-six active adults completed a single 90min session involving alternating intervals of exercise (5min) and recovery (10min). Exercise involved walking (4km/h), jogging (8km/h), running (12km/h) or a sport-simulated circuit (three intervals). Participants wore two triaxial accelerometers (GT3X+ and SWA) and a portable gas analyser (MetaMax 3B), used as the criterion measure., Results: Total EE was significantly underestimated (p<0.01) by the GT3X+ (mean bias±SD: -374.5±132.84kJ; % difference=-29.3%) and SWA (-244.3±148.0kJ; -18.2%). Overestimations were made by both accelerometers during the walk (GT3X+: 27.4±30.8kJ; SWA: 32.1±15.4kJ) and jog (38.0±30.0kJ; 34.5±31.6kJ). Underestimations were evident during the run (-41.2±25.1kJ; -43.8±33.5kJ) and circuit (C1: GTX+: -127.2±41.6kJ; SWA: -86.1±40.2kJ). Error of estimation increased in magnitude as the intensity of exercise increased (GT3X+: 40.8-143.0kJ; SWA: 35.5-102.0kJ)., Conclusions: The ActiGraph GT3X+ and BodyMedia SWA do not provide valid EE estimates across a range of exercise modalities and intensities when compared to a criterion measure. Poor accuracy and large precision errors, particularly during high intensity and intermittent movement patterns, suggest these devices have limitations and should be used cautiously in the field., (Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Effects of early and permanent footwear use are not well understood. The aim of this study was to investigate the effects of habituation to footwear on foot strike patterns of children and adolescents. Healthy habitually barefoot and shod participants (aged 6-18 years) from South Africa (n=288) and Germany (n=390) performed multiple 20-m jogging and running trials with and without shoes. Each foot strike was captured using a high-speed camera to determine a rearfoot or non-rearfoot strike. The probability of a rearfoot strike in both cohorts and each age was analyzed by using a mixed-effects logistic regression adjusted for possible confounders. Habitually barefoot children showed a higher probability of using rearfoot strikes than habitually shod children (p<0.001). The probability was age-dependent and decreased in habitually barefoot children with age (OR barefoot-jogging =0.82, 95% CI, 0.71 to 0.96, p=0.014; OR barefoot-running =0.58, 95% CI, 0.50 to 0.67, p<0.001 and OR shod-running =0.68, 95% CI, 0.59 to 0.79, p<0.001). In habitually shod children, the probability increased significantly for shod jogging (OR=1.19, 95% CI, 1.05 to 1.35, p=0.006). To conclude, foot strike patterns of children are influenced by habituation to footwear. Younger habitually barefoot children show higher rates of rearfoot strikes for shod and barefoot running, and it converges in later adolescence., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (© Georg Thieme Verlag KG Stuttgart · New York.)

The acute urge to be physically active is a relevant clinical phenomenon in patients suffering from eating disorders. In this study with n = 20 female patients with anorexia nervosa and n = 10 female patients with bulimia nervosa, a virtual reality (VR) jogging paradigm was applied as a novel highly immersive 3D exposure paradigm. Patients were asked to rate their acute urge to be physically active during the exposure procedure. A 10-item self-report questionnaire (smQ) was developed to capture the cognitive, emotional, and behavioral aspects of the acute urge to move. We hypothesized that exposure would lead to habituation of the urge to be physically active. We also hypothesized that leptin levels would be associated with the degree of the subjective urge to be physically active, while habituation would be associated with a decrease in stress hormones (α-amylase, cortisol, and cortisone in saliva). A statistically significant change in subjective scores in the smQ from baseline to postexposure was seen. Our novel VR paradigm may serve as a therapeutic tool for exposure and habituation of the urge of acutely engaging in physical activity in patients with eating disorders., (© 2017 Wiley Periodicals, Inc.)

Background: It is unknown whether the height of a heel-rise performed in the single-leg standing heel-rise test 1 year after an Achilles tendon rupture (ATR) correlates with ankle biomechanics during walking, jogging, and jumping in the long-term., Purpose: To explore the differences in ankle biomechanics, tendon length, calf muscle recovery, and patient-reported outcomes at a mean of 6 years after ATR between 2 groups that, at 1-year follow-up, had less than 15% versus greater than 30% differences in heel-rise height., Study Design: Cohort study; Level of evidence, 3., Methods: Seventeen patients with less than 15% (<15% group) and 17 patients with greater than 30% (>30% group) side-to-side difference in heel-rise height at 1 year after ATR were evaluated at a mean (SD) 6.1 (2.0) years after their ATR. Ankle kinematics and kinetics were sampled via standard motion capture procedures during walking, jogging, and jumping. Patient-reported outcome was evaluated with Achilles tendon Total Rupture Score (ATRS), Physical Activity Scale (PAS), and Foot and Ankle Outcome Score (FAOS). Tendon length was evaluated by ultrasonography. The Limb Symmetry Index (LSI = [Injured Side ÷ Healthy Side] × 100) was calculated for side differences., Results: The >30% group had significantly more deficits in ankle kinetics during all activities compared with patients in the <15% group at a mean of 6 years after ATR (LSI, 70%-149% and 84%-106%, respectively; P = .010-.024). The >30% group, compared with the <15% group, also had significantly lower values in heel-rise height (LSI, 72% and 95%, respectively; P < .001) and heel-rise work (LSI, 58% and 91%, respectively; P < .001) and significantly larger side-to-side difference in tendon length (114% and 106%, respectively; P = .012). Achilles tendon length correlated with ankle kinematic variables ( r = 0.38-0.44; P = .015-.027) whereas heel-rise work correlated with kinetic variables ( r = -0.57 to 0.56; P = .001-.047). LSI tendon length correlated negatively with LSI heel-rise height ( r = -0.41; P = .018). No differences were found between groups in patient-reported outcome ( P = .143-.852)., Conclusion: Height obtained during the single-leg standing heel-rise test performed 1 year after ATR related to the long-term ability to regain normal ankle biomechanics. Minimizing tendon elongation and regaining heel-rise height may be important for the long-term recovery of ankle biomechanics, particularly during more demanding activities such as jumping.

Medial tibial stress syndrome (MTSS) is one of the most common exercise-induced leg pain. The navicular drop (ND) was identified as a risk factor for MTSS. This study aimed to evaluate the short-term effects of sports taping applied to the supporting lower leg during sitting, standing, walking, and jogging to restrict the ND in healthy elite athletes.Twenty-four healthy elite athletes without a history of exercise-induced pain or injuries in the lower limbs participated in this study (median age: 21.00 years; 1st--3rd quartiles; 19.25-22.00). The 4 taping conditions were used: rigid taping (RT), kinesiology taping (KT), placebo taping (PT), and non-taping (NT). The order of taping techniques was randomly assigned. Normalized navicular height (NH), ND, and normalized ND evaluated using 3-dimensional motion analysis, and normalized peak plantar pressure (PP) were compared in 4 taping conditions during sitting, standing, walking, and jogging.During sitting, the normalized NH of RT is higher than that of NT, KT, and PT (χ = 17.30, P = .001), while during jogging, the normalized NH of RT is higher than that of NT and PT (χ = 10.55, P = .014). The normalized peak PP of NT is higher than that of PT (χ = 8.871, P = .031) in the lateral midfoot region.This study showed the RT technique maintained NH during sitting and jogging, and the RT technique could be an effective preventive and treatment strategy for MTSS.

A limited number of studies have explored lower-limb biomechanics during high-heeled jogging and running, and most studies have failed to clarify the wearing experience of subjects. This protocol describes the differences in lower-limb kinematics and ground reaction force (GRF) between experienced wearers (EW) and inexperienced wearers (IEW) during moderate high-heeled jogging and running. A three-dimensional (3D) motion analysis system with a configured force platform was used to synchronously capture lower-limb joint movements and GRF. 36 young females volunteered to participate in this study and were asked about high-heeled shoe-wearing experience, including frequency, duration, heel types, and heel heights. Eleven who had the experience of 3 to 6 cm heels for a minimum of three days per week (6 h per day) for at least two years and eleven who wore high heels less than twice per month participated. Subjects performed jogging and running at comfortable low and high speeds, respectively, with the right foot completely stepping onto a force platform when passing by along a 10 m walkway. EW and IEW adopted different biomechanical adaptations while jogging and running. IEW exhibited a generally larger range of joint movement, while EW showed a dramatically larger loading rate of GRF during running. Hence, further studies on the lower-limb biomechanics of high-heeled gait should strictly control the wearing experience of the subjects.

Background: Assessment of health benefits associated with physical activity depend on the activity duration, intensity and frequency, therefore their correct identification is very valuable and important in epidemiological and clinical studies. The aims of this study are: to develop an algorithm for automatic identification of intended jogging periods; and to assess whether the identification performance is improved when using two accelerometers at the hip and ankle, compared to when using only one at either position., Methods: The study used diarized jogging periods and the corresponding accelerometer data from thirty-nine, 15-year-old adolescents, collected under field conditions, as part of the GINIplus study. The data was obtained from two accelerometers placed at the hip and ankle. Automated feature engineering technique was performed to extract features from the raw accelerometer readings and to select a subset of the most significant features. Four machine learning algorithms were used for classification: Logistic regression, Support Vector Machines, Random Forest and Extremely Randomized Trees. Classification was performed using only data from the hip accelerometer, using only data from ankle accelerometer and using data from both accelerometers., Results: The reported jogging periods were verified by visual inspection and used as golden standard. After the feature selection and tuning of the classification algorithms, all options provided a classification accuracy of at least 0.99, independent of the applied segmentation strategy with sliding windows of either 60s or 180s. The best matching ratio, i.e. the length of correctly identified jogging periods related to the total time including the missed ones, was up to 0.875. It could be additionally improved up to 0.967 by application of post-classification rules, which considered the duration of breaks and jogging periods. There was no obvious benefit of using two accelerometers, rather almost the same performance could be achieved from either accelerometer position., Conclusions: Machine learning techniques can be used for automatic activity recognition, as they provide very accurate activity recognition, significantly more accurate than when keeping a diary. Identification of jogging periods in adolescents can be performed using only one accelerometer. Performance-wise there is no significant benefit from using accelerometers on both locations.

Walking, slow running (jogging) and fast running often occur in daily life, Physical Education Class and Physical Fitness Test for children. However, potential impact of jogging and running on plantar pressure of children is not clear. The purpose of this study was to compare the characteristics of plantar pressure distribution patterns in obese and non-obese children during walking, jogging and running, and evaluate biomechanical effects of three movements on obese children. A 2-m footscan plantar pressure plate (RSscan International, Belgium) was used to collect the gait data of 20 obese children (10.69±2.11years; 1.51±0.11m; 65.15±14.22kg) and 20 non-obese children (11.02±1.01years; 1.48±0.07m; 38.57±6.09kg) during three movements. Paired t-test and independent sample t-test were performed for statistical comparisons and ANOVA was used for comparisons of gait characteristics among three movements. Significance was defined as p <0.05. Propulsion phase during jogging for obese children was the longest among three movements (p=0.02). Peak pressures under metatarsal heads IV, V (M4, M5), midfoot (MF), heel medial (HM) and heel lateral (HL) during jogging for obese children were the highest among three movements (p=0.005, p=0.003, p=0.004, p=0.03, p=0.01). Arch index (AI) of left foot during jogging for obese children was the largest (p=0.04)., Conclusions: Plantar pressure distribution during three movements changed differently between two groups. The peak pressures under most plantar regions and AI during jogging for obese children were the largest among three movements, indicating that jogging caused more stress to their lower extremities. Obese children perhaps should not consider jogging as regular exercise., (Copyright © 2017. Published by Elsevier B.V.)

The aim of the present study was to examine reliability and construct convergent validity of Player Load™ (PL) from trunk-mounted accelerometry, expressed as a cumulative measure and an intensity measure (PL · min - 1 ). Fifteen male participants twice performed an overground football match simulation that included four different multidirectional football actions (jog, side cut, stride and sprint) whilst wearing a trunk-mounted accelerometer inbuilt in a global positioning system unit. Results showed a moderate-to-high reliability as indicated by the intra-class correlation coefficient (0.806-0.949) and limits of agreement. Convergent validity analysis showed considerable between-participant variation (coefficient of variation range 14.5-24.5%), which was not explained from participant demographics despite a negative association with body height for the stride task. Between-task variations generally showed a moderate correlation between ranking of participants for PL (0.593-0.764) and PL · min - 1 (0.282-0.736). It was concluded that monitoring PL ® in football multidirectional actions presents moderate-to-high reliability, that between-participant variability most likely relies on the individual's locomotive skills and not their anthropometrics, and that the intensity of a task expressed by PL · min - 1 is largely related to the running velocity of the task.

Recreational running encompasses more than one type of exercise. Different running practices offer different, even opposing, conceptualisations of the role of the environment. As illustrated in this paper, historical studies can uncover and explain these variations. By studying the clash between two practices in Sweden in the 1970s - the newly translated idea of North American jogging and an already established tradition of fitness running - this paper qualifies the difference between them and illustrates how they assembled competing geographies. The paper argues that current planning would benefit from acknowledging this multiplicity because different forms of running offer complementary strategies for inclusivity., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Youth who are obese have high risk of poor knee health and cartilage damage. Understanding factors which may affect knee health in youth who are obese is critical for preservation of knee integrity and function., Objective: This study compared standing frontal-plane knee alignment and knee loading patterns between youth who are obese and those of healthy weight and determine the association between knee alignment and knee loading patterns during walking and jogging., Design: This study used a cross-sectional matched pair design., Methods: Twenty youth who were obese and 20 youth who were healthy-weight (ages 11-18 years) were recruited. Three-dimensional motion analysis quantified standing frontal-plane knee alignment as well as frontal- and sagittal-plane knee moments during walking and jogging. Paired t -tests, multiple analysis of covariance, and Spearman's rank correlation coefficients were used for analysis., Results: The youth who were obese demonstrated greater knee valgus in standing ( P  = 0.02), lower normalized peak external knee adduction moments during walking ( P  = 0.003), and greater normalized peak external knee extension moments during jogging ( P  = 0.003) compared with the youth who were healthy-weight. Standing knee alignment did not correlate with knee moments in the youth who were obese., Limitations: Results are limited to small, homogeneous cohorts. The standing alignment methodology is not validated in this population and may limit interpretation of results., Conclusion: Youth who are obese stand in more knee valgus and have altered knee loading patterns during walking and jogging compared with youth who are healthy-weight. Frontal-plane knee alignment does not correlate with frontal-plane knee loading patterns in youth who are obese. A better understanding of other mechanisms related to joint loading in youth who are obese is necessary to maintain long-term joint integrity in this population., (© 2017 American Physical Therapy Association)

Background: In recent years, an increasing number of runners prefer jogging barefoot or in minimalistic shoes. The aim of this study was to compare the distribution of plantar pressure during jogging barefoot, in minimalistic shoes, or in shoes with cushioned soles, as these forces modulate the risk of injury., Methods: The study included nine men aged between 24 and 25 years, who engaged in long-distance running. The plantar pressure of three foot zones (forefoot, midfoot, and hindfoot) was examined with WIN-POD electronic podometer during running barefoot, in minimalistic shoes, or in shoes with cushioned soles., Results: Individuals who ran barefoot showed the greatest forefoot pressure, followed by those running in minimalistic shoes and cushioned shoes. In contrast, the heel pressure in individuals running in cushioned shoes was significantly greater than in those using minimalistic shoes or running barefoot., Conclusions: Switching from running in cushioned shoes to jogging barefoot is associated with the accumulation of greatest pressure in the forefoot and midfoot. The accumulation of the greatest pressure at the insertion of plantar aponeurosis can lead to the injuries of musculoskeletal system, in particular plantar aponeurositis. Even distribution of pressure among various parts of the foot in persons running in minimalistic shoes is associated with lower risk of injury than in the case of running barefoot.

Purpose: We developed a short-interval, low-intensity, slow-jogging (SJ) program consisting of sets of 1 min of SJ at walking speed and 1 min of walking. We aimed to examine the effects of an easily performed SJ program on skeletal muscle, fat infiltration, and fitness in older adults., Methods: A total of 81 community-dwelling, independent, older adults (70.8 ± 4.0 years) were randomly assigned to the SJ or control group. The SJ group participants were encouraged to perform 90 min of SJ at their anaerobic threshold (AT) intensity and 90 min of walking intermittently per week. Aerobic capacity at the AT and sit-to-stand (STS) scores were measured. Intracellular water (ICW) in the legs was assessed by segmental multi-frequency bioelectrical impedance analysis. Subcutaneous (SAT) and intermuscular (IMAT) adipose tissue and muscle cross-sectional area (CSA) were measured at the mid-thigh using computed tomography., Results: A total of 75 participants (37 SJ group, 38 controls) completed the 12-week intervention. The AT and STS improved in the SJ group compared with the controls (AT 15.7 vs. 4.9 %, p < 0.01; STS 12.9 vs. 4.5 %, p < 0.05). ICW in the upper leg increased only in the SJ group (9.7 %, p < 0.05). SAT and IMAT were significantly decreased only in the SJ group (p < 0.01)., Conclusion: The 12-week SJ program was easily performed by older adults with low skeletal muscle mass, improved aerobic capacity, muscle function, and muscle composition in older adults.

This study examined the effects of regular Tai Chi practice and jogging on the neuromuscular activity of the trunk, hip, and ankle joint muscles of older people during lateral postural perturbation. A total of 42 older people participated in the study and formed the Tai Chi, jogging, and sedentary control groups. Electromyography signals were collected from the peroneus longus, anterior tibialis, gluteus medius, and erector spinae during unpredictable mediolateral perturbation. The Tai Chi group exhibited significantly faster latencies of the tibialis anterior and erector spinae than the control group. The jogging group showed a significantly shorter neuromuscular reaction time of the erector spinae than the control group. No significant difference was observed between the Tai Chi and jogging groups. Long-term regular Tai Chi practice enhanced the neuromuscular reaction of the erector spinae and tibialis anterior to lateral perturbation and will help timely posture correction when lateral postural distributions occur.

Purpose: The main purpose of this study was to examine the accuracy of wristband activity monitors on measuring step counts at prescribed speeds on a treadmill and under short bouts of common daily activities., Methods: Thirty healthy young adults wore three wristband activity monitors on both wrists while walking or jogging on a treadmill at different speeds (54, 80, 107, and 134 m·min) and performing six different common daily activities for 5 min each. The monitors included the Fitbit Flex, the Garmin Vivofit, and the Jawbone UP. The common daily activity conditions included two sitting activities (playing a tablet computer game and folding laundry), two walking activities (pushing a stroller, carrying a bag), and two stair climbing activities (down and up). Absolute percentage error (APE) scores were computed to examine the accuracy between actual observed steps and monitor-detected steps., Results: Under the treadmill condition, the APE ranged between 1.5% and 9.6%. Accuracy was improved at faster speeds (134 m·min) for all the monitors (APE < 2.5%). In the common daily activity conditions, substantial step counts were registered when folding laundry. All monitors significantly underestimated actual steps (all APE >33%) when pushing a stroller. Higher APE was observed when worn on the dominant wrist under the common daily activity conditions., Conclusions: The wristband activity monitors examined were more accurate for measuring step counts between 80 and 134 m·min as compared with a slower speed. Accuracy under each common daily activity condition ranged widely between monitors and activity, with less error when worn on the nondominant wrist. These results will help to inform researchers on the use and accuracy of wristband activity monitors for future studies.